Self-cleaning dust-separator.



F. GRAFFENBERGER.

sen CLEANING DUST SEPARATOR.

APPLICATION FILED MN- IBIO.

1w Apr. 27, 1915.

VE/v Tam l i wim m Jljllli m FRIEDRICH GRAFFENBERGER, 0F MILWAUKEE, WISCONSIN.

SEIJF-CLEANING DUST-SEPARATOB.

Specification of Letters Patent.

Patented Apr. 27, 1915.

Application filed January 17, 1910/ Serial No. 538,407.

To all whom'it may concern:

Be it known that I, FRIEDRICH GRAFFEN- BERGER, residing in Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Self-Cleaning Dust-Separators, of which the following is a description, reference being bad to the accompanying drawings, which are a part of this specification.

This invention has for its object to provide a dust separator for vacuum cleaning systems in which the dust separating material may be cleaned without disconnecting the parts.

Another object of the invention is to provide a dust separator which will automatically indicate to the operator when the dust separating material thereof is in a tion to require cleaning.

Another object of the invention is to provide a dust separator containing a strainer cloth or the like of a cylindrical form with means for imparting tension thereto and adapted to flex said strainer cloth and then quickly apply tension thereto for throwing the accumulated dust from the strainer cloth, there preferably being a scraper to travel around the cylindrical strainer cloth to assist in removing the dust.

With the above and other objects in view the invention consists in the self cleaning dust separator herein disclosed, its parts and combinations of parts as claimed, and all equivalents.

In the accompanying drawing I show an' exemplifying structure embodying the invention, but it is to be understood that the invention is capable of embodiment in different forms. v

Referring to the accompanying drawings in which llke characters of reference indicate the same parts in the different views: Figure 1 is a central sectional view of a self cleaning dust separator constructed in accordance with this invention; Fig. 2 is a plan view thereof; Fig. 3 is a detail view of the clean-outdoor; and, Fig. 4 is a detail view of one of the strainer stem projections and the stationary roller with which it engages.

In these drawings indicates a blower or air pump of any desired construction to create the vacuum for cleaning purposes and 11 is a tubular connection leading therefrom to the dust separator of this invention, as here shown such connection forming condithe lower extension of a tubular standard 12 contained within the casing. The casing is formed by a bottom plate 13, preferably integral with the standard 12, 14, with a cylindrical side Wall 15 clamped between them by means of bolts 16 extending from one end plate to the other. The cylindrical side Wall 15 fits within packed grooves of the end plates 13 and 14 to form air tight joints therewith, so that the suction from the air pump 10 will produce its full effect upon the suction hose connection 17 leading from the top plate 14:, the air from the suction hose passing through the casing on its way to the air pump.

Removablv mounted on the tubular standaid 12 is the lower disk shaped head 18 of the strainer, the upper disk shaped head 19 thereof being loosely mounted on a stem 20 which slidably fits in a'bushing or bearing 21 in the top plate 14. Each of these disk shaped heads 18 and 19 is provided with an annular grooved flange at its periphery to form a convenient engaging seat for a band 22 of wire or other material for firmly connecting to it the ends of a cylindrical strainer cloth 23,-which may be of any fabric suitable for the purpose of separatingdust from dust laden air. The strainer cloth 23 is held under tension by reason of a coil spring 24 surrounding the stem 20 and hearing at ,one end against the top plate 14 and at the other end against a pair of set nuts 25 threaded on the stem. The stem is capable of move- .ment downwardly by compressing the spring 24, so-as .to lower the upper head 19 of the strainer and thus ,flex the strainer fabric, and mechanical means are provided for producing such movement of the upper head with a quick return movement for the purpose of snapping the fabric violently from its flexed condition into its condition of tension to throw the accumulated dust therefrom. As here shown such means may a i comprise one or more projections 26 on the stem 20 adapted to be turned by means of handles 27 also mounted on the stem to be brought into engagement with a stationary roller 28- mounted on the top plate 14 by means .of an arm 29. The handles 27 are preferably secured to the stem by forming them on a sleeve which is threaded "on the stem and is then looked thereto by means of a pin passing through the sleeve and the stem and the projection 26 are desirably secured on the stem in a like manner. The

and a top plate their remalning in the position in which they engage the roller 28, to facilitate the ,5 assembling of the parts.

In order that the strainer cloth may be further relieyed of dust adhering to the outside thereof by a scraping action, one or more arms 30 may be secured to the stem 20 with downwardly extending rods 31 mounted on their outer ends and traveling close to the strainer cloth during the rotary movements of the stem, so that a scraper blade 33 of rubber or the like secured thereto may bear against the outer surface of the strainer cloth and scrape thedust therefrom. The dust removed from the strainer drops to the funnel shaped bottomplate 13 of the casing, where it is brushed into a pocket 34 by means of scrapers 35 of leather or other flexible material which will bear on the bottom of the casing and will yield to permit the downward movement of the rods 31. The mouth. or opening of the pocket 34 is clamped in position by a set screw 37 car ried on an arm 88 which is pivotallymounted on one side of the pocket and engages a headed pin 39 on the other side of the pocket with its hook-shaped end. The cover 36 is caused to swing with the arm 38 by having headed pins 40 thereon slidably passing through the arm.

In operation, the hose connection 17 is connected with a suction hose'bearing the cleaning tool and the air pump 10 is set in operation to produce suction at the tool'and to convey the dust laden air therefrom through the dust separator, the dust being strained from the air when the latter passes through the strainer cloth. The force of the spring 20 is suflicient to hold the strainer cloth approximately straight, vertically, when the latter is'free from dust, but when its meshes become clogged with the dust lodged therein and adhering to the surface of the cloth the resistance to the passage of air becomes greater, with the result that there will be a perceptible downward movement of the stem 20 and the parts are carried thereby whenever the cleaning tool is lifted from engagement with. the material being cleaned, the resistance of the strainer cloth to the increased flow of air at such times being sufficient to cause it to be drawn inwardly against the action of the spring. This motion of the stem and the parts carried thereby serves as an indicator to notify the operator that the strainer cloth has an accumulation of dirt which is required to be removed inorder to produce eflicient operation. He then stops the operation of the pump and turns the handles 27, thereby carrying the scraper blades 33 around the surface of the strainer cloth to remove the dirt hermetically sealed by means of a cover 36 ing the strainer cloth the clean out opening is employed as a means for access to the lower head 18 of the strainer. For removing a worn strainer cloth, it is only necessary to reach through the clean out opening and loosen the clamping screw 18' of the lower head 18, so that said head 18 is free to slide off of the tapering upper end of the tubular standard 12, when the cover plate 14 may be withdrawn from the remainder of the casing by releasing it from the bolts 16, the head 18 moving therewith. When the parts are thus separated the strainer cloth may be removed from the heads 18 and 19 and a new one substituted therefor, and the top plate 14 is then returned to its place and clamped in position while the lower head 18 of the strainer is guided into place on the tubular stem 12 by reaching the arm through the clean out opening, and while the stem 20 is held in its lower position with the roller 28 engaged with the flat surface of the projection 26, the head 18 is drawn down on the tubular standard 12 until the strainer cloth is nearly as tight as it should be in use, and then the clamping screw of the head 18 is tightened. When the stem is then turned to remove the projection 26 from the roller 28 the spring 2-1 stretches the strainer fabric to the proper tension, care bein taken that the difference between the condition of adjustment and the condition. when under tension produced by the spring will be sufficient to cause the snapping action of the strainer cloth when the projection 26 passes beneath the roller 28 for cleaning the as above described. I

I desire it to be understood that this invention as claimed is not limited to any specific form or arrangement of parts excloth cept in so far as such limitations are specia stem slidably and rotatably mounted therein, a flexible screen within the casing supported by the stem, an arm fixed on the stem, a scraper blade carried thereby for scraping the flexible screen, for holding the stem in its upper position, means for turning the stem, and means operated by the turning movement of-the stem for causing the stem to move downwardly.

3. A dust separator, comprising a cylindrical casin having a discharge passageway in the ottom thereof, a stem slidably and rotatably mounted in the casing, a flexible screen within the casing having its upper end supported by the stem, an arm cara spring means ried by the stem, a scraper blade carried by the arm for engaging the flexible screen and a scraper also carried by the arm for scraping the material from the bottom of the casing into the discharge passageway thereof, means for turning the stem and means for reciprocating the stem incident to its turning movements.

In testimony whereof, I afiix my signature, in presence of two Witnesses.

FRIEDRICH GRAFFENBERGER.

Witnesses:

R. S. C. CALDWELL, ALMA A. KLU 

